plunge

The children laughed as they prepared to plunge into the cold ocean waves.

(Chinese) 孩子们准备纵身跳入冰冷的海浪中时发出了笑声。

He took a deep breath and plunged his hands into the icy mountain stream.

(Chinese) 他深吸一口气，把手伸进冰冷的山间溪流中。

The sudden plunge in the stock market caused panic among many small investors.

(Chinese) 股市的突然骤降引起了许多小投资者的恐慌。

After the hike, we felt refreshed by a quick plunge in the cool lake.

(Chinese) 徒步旅行后，在凉爽的湖中快速浸泡（纵身一跳）让我们感到精神焕发。